Building bass traps into the ceiling?

[QuadDiffuser]

Fundamentally (and primarily), the 30/40/50/60Hz (and all of the frequencies in between) "issues" are coming from the loudspeakers (source) and the shortest dimensions in the boundaries of listening room (floor to ceiling). Therefore, the most logical (and aesthetically acceptable) locations for the bass absorbers are above the bass ports and bass drivers of the loudspeakers.

 

[PaulB]

I use PSI Audio/Switzerland AVAA active bass traps with very good results.

PSI Audio AVAA Bass Traps

 

[QuadDiffuser]

I also use PSI Audio's AVAAs - four (4) of them!

PSI Audio AVAA C20 Active Bass Absorber

All fair enough, Matts! Thank you very much for posting here. We are delighted to see you!

www.whatsbestforum.com

 

[christoph]

I use PSI Audio/Switzerland AVAA active bass traps with very good results.

PSI Audio AVAA Bass Traps

Could you elaborate some?

 

[christoph]

I also use PSI Audio's AVAAs - four (4) of them!

PSI Audio AVAA C20 Active Bass Absorber

All fair enough, Matts! Thank you very much for posting here. We are delighted to see you!

www.whatsbestforum.com

please elaborate on your results

 

[QuadDiffuser]

Hi Christoph! Posting the following link (for the second time):

PSI Audio AVAA C20 Active Bass Absorber

All fair enough, Matts! Thank you very much for posting here. We are delighted to see you!

www.whatsbestforum.com

 

[barryr1]

Has anyone got experience of building bass traps into the ceiling? We're about to replace our listening room ceiling (that is also our living room), and wondering if I should consider integrating some sound treatment at the same time. Am specifically looking at treating a 50Hz peak in a room ~11m x 5m.

I have 2 large 4x8’ bass traps built into the ceiling. Acoustic engineered. My recollection is they have 15” of acoustic batt insulation behind the wooden slats

 

[M3bird]

PSI Audio AVAA is Good https://www.aria-audio.com/en/products/avaa-c20

 

[brad225]

Building my room in 2013 I chose to build soffit traps as Bruce Brown did. I framed down 10" x 16" wide around the room. This is open to the dead space above the ceiling. I filled the soffit and 3' wide and the varying height in the ceiling. I made frames and covered it with the same Gulf of Maine fabric as the walls.

 

[QuadDiffuser]

Recently I discovered Silk Metal, a micro-perforated metal grilles which has a very linear absorption curve in the mid-to high frequencies, as well as deep absorption below 400Hz when used with an air gap. Details are posted in my basement listening room thread - click the red link below:

My dedicated audio room build - QuadDiffusor's Big Dig

There is of course another room acoustical technology that provides a third approach to dealing with low frequencies. Developed for and in use by well known film/recording/mixing studios (links to examples below), it is based on very high numbers per sf of non-parallel surfaces (DHDI ZR...

www.whatsbestforum.com

Lab measurements suggest that the Silk Metal tiles in drop-in grilles are more effective as ceiling bass traps than simple soffits filled with building insulation material.

 

[Ron Resnick]

Welcome to WBF, M3bird!

What has been your specific experience with the AVAAs?

 

[Kingrex]

I recognized the importance of bass pressure alleviation, and wanted to utilize my ceiling space to install bass traps into the ceiling of my listening space in my apartment. Down below to the L is the front wall which is treated with P-17 Quadratic diffusors, and down below to the R is where the listening sofa is located. Thankfully, my ceiling is 10ft. high, which allows installation of these large and extremely heavy modules - closest to the L are five diaphragmatic bass absorbers (16" deep x 27" square) tuned to deeply absorb between 30-50Hz; next are 5 pcs. of diaphragmatic bass absorbers (14" deep x 27" square), tuned to broadly (but less deeply) absorb frequencies between 50-200Hz; then a row of five Prime-13 quadratic diffusors which horizontally scatter frequencies between 285 Hz. and 3,450 Hz. These are installed in a lattice of steel frames (visible through the dark voids), criss-crossing and anchored to the structural columns and beams of my apartment building to provide stability and solidity. These were all built to custom specifications and sizes at great cost and required herculean effort to install. Please PM me if you'd like to find out more information. View attachment 50879

Nice ceiling. I was thinking the whole ceiling should have plywood backing with drywall over the top. That way you can support most anything. You seem to have gone with a light weight steel I beam the achieve the same ability to support fairly heavy loads. I like your method better as the devices could be on rollers over the edges of the I beam and easily moved to fine tune the placement. It could even be done with pocket door rail on the ceiling.

 

[QuadDiffuser]

Recently I discovered Silk Metal, a micro-perforated metal grilles which has a very linear absorption curve in the mid-to high frequencies, as well as deep absorption below 400Hz when used with an air gap. Details are posted in my basement listening room thread - click the red link below:

My dedicated audio room build - QuadDiffusor's Big Dig

There is of course another room acoustical technology that provides a third approach to dealing with low frequencies. Developed for and in use by well known film/recording/mixing studios (links to examples below), it is based on very high numbers per sf of non-parallel surfaces (DHDI ZR...

www.whatsbestforum.com

Lab measurements suggest that the Silk Metal tiles in drop-in grilles are more effective as ceiling bass traps than simple soffits filled with building insulation material.

I examined a sample of the Silk Metal micro-perforated plates and determined that it was unfortunately totally unsuitable as a broadband absorption insertion into a drop-ceiling grid; hundreds/thousands of mechanical connection points (between the plates and the grids) will be a source of unacceptable mechanical "pinging" noises which can't be suppressed in any reliable way, short of perhaps applying gobs of viscous silicon glue into every single point of contact.

 

[henrich3]

It's easier to tame room modes below 100 Hz by adding another subwoofer & adjusting their positioning or delays rather than using acoustic panels. I had a 7 dB mode at 45 Hz and a null around 70 Hz. Increasing the delay in one of my two subs solved both of those problems.

There's some useful info on room modes here -
https://forum.blu-ray.com/showthread.php?t=48286

 

[QuadDiffuser]

Thank you, henrich3, for the link - I agree with your advice. For my future dedicated listening room, I just want to ensure that the room acoustics can support the addition of two subwoofers without any anomalies which I'll later regret. Instead of line-level inputs, I'm likely going with subwoofers with high-voltage "speaker level" inputs, tapping the voltage/current from the amplifier from the bi-wired speaker bass binding posts, and routing it to the subwoofer. Von Schweikert Audio uses this strategy with their own external subwoofers for their Ultra line of loudspeakers, with excellent results.